Most professional teachers will be strict, often call the roll and have many names.

Most teachers in elective courses and non-professional courses do not often call the roll.

Knowledge expansion:

Universities are cultural institutions with unique functions, institutions of higher learning that inherit, research, integrate and innovate advanced academic knowledge, and are interrelated with social, economic and political institutions. It is not only the product of the development of human culture to a certain stage, but also a unique university culture gradually formed on the basis of long-term school-running practice through historical accumulation, self-efforts and the influence of external environment.